Which of the following tasks can a dental hygienist NOT perform independently?

A dental hygienist is typically allowed to perform a variety of tasks that fall within their scope of practice, such as applying topical fluoride, etching enamel surfaces, and taking impressions for dental casts. However, administering local anesthesia requires a higher level of training and expertise, which is why this task is not considered something that they can perform independently.

The administration of local anesthesia involves a detailed understanding of anatomy, pharmacology, and the management of possible complications that may arise during the procedure. These skills are typically part of advanced training that goes beyond the qualifications of a dental hygienist. In many jurisdictions, this procedure is reserved for dentists or dental professionals with specialized training in anesthesia administration. Thus, while dental hygienists can assist in many important roles in patient care, the independent administration of local anesthesia remains outside of their usual scope of practice.